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91.
92.
The amygdala is a subcortical structure implicated in both the expression of conditioned fear and social fear recognition. Social fear recognition deficits following amygdala lesions are often interpreted as reflecting perceptual deficits, or the amygdala''s role in coordinating responses to threats. But these explanations fail to capture why amygdala lesions impair both physiological and behavioural responses to multimodal fear cues and the ability to identify them. We hypothesized that social fear recognition deficits following amygdala damage reflect impaired conceptual understanding of fear. Supporting this prediction, we found specific impairments in the ability to predict others'' fear (but not other emotions) from written scenarios following bilateral amygdala lesions. This finding is consistent with the suggestion that social fear recognition, much like social recognition of states like pain, relies on shared internal representations. Preserved judgements about the permissibility of causing others fear confirms suggestions that social emotion recognition and morality are dissociable.  相似文献   
93.
The stomach contents of 196 razorfish ( Xyrichthys novacula ), collected in the Tyrrhenian Sea (Ponza Island, Italy) between July and December 1994, were examined in order to assess the diet and to analyse size-related dietary variation of the species. The diet of X. novacula showed a strict relationship with well-sorted fine sand (SFBC) benthic species, mostly Mollusca and Echinodermata, as pointed out by the analysis at the specific level of the stomach contents. Mollusca Pelecipoda, essentially Acanthocardium tuberculatum and Echinodermata, with Echinocardium cordatum , made up 90% of the volume of prey of X. novacula. Mysidacea and Gastropoda were frequent but volumetrically less important. The study showed that male and female X. novacula were not effectively segregated by trophic dimension in the study area. The niche overlap between males and females in prey composition was pronounced, as evidenced by the significantly high values of Schoener's index with larger males that showed a greater tendency towards predation of large prey. The increment in length (L.I.) in males, despite a decrease in the percentage body weight increment (B.W.I.), could represent the result of a male reproductive feature: the lack of sperm competition allows the males much more energy to devote to growth than do that of the females of this species.  相似文献   
94.

Background  

Glycogen Synthase Kinase-3 (GSK3) activity is repressed following insulin treatment of cells. Pharmacological inhibition of GSK3 mimics the effect of insulin on Phosphoenolpyruvate Carboxykinase (PEPCK), Glucose-6 Phosphatase (G6Pase) and IGF binding protein-1 (IGFBP1) gene expression. CAAT/enhancer binding protein alpha (C/EBPα) regulates these gene promoters in liver and is phosphorylated on two residues (T222/T226) by GSK3, although the functional outcome of the phosphorylation has not been established. We aimed to establish whether CEBPα is a link between GSK3 and these gene promoters.  相似文献   
95.

Background

Cancer immunoediting is a dynamic process composed of three phases: elimination (EL), equilibrium (EQ) and escape (ES) that encompasses the potential host-protective and tumor-sculpting functions of the immune system throughout tumor development. Animal models are useful tools for studying diseases such as cancer. The present study was designed to characterize the interaction between mammary adenocarcinoma M-406 and CBi, CBi and CBi/L inbred mice lines.

Results

The mammary adenocarcinoma M-406 developed spontaneously in a CBi mouse. CBi/L and CBi mice were artificially selected for body conformation from CBi. When CBi mice are s.c. challenged with M-406, tumor growths exponentially in 100% of animals, while in CBi the tumor growths briefly and then begins a rejection process in 100% of the animals. In CBi/L the growth of the tumor shows the three phases: 51.6% in ES, 18.5% in EQ and 29.8% in EL.

Conclusions

The results obtained support the conclusion that the system M-406 plus the inbred mouse lines CBi, CBi and CBi/L, is a good murine model to study the process of tumor immunoediting.  相似文献   
96.
For algal biofuels to become a commercially viable and sustainable means of decreasing greenhouse gas emissions, growers are going to need to design feedstocks that achieve at least three characteristics simultaneously as follows: attain high yields; produce high quality biomass; and remain stable through time. These three qualities have proven difficult to achieve simultaneously under the ideal conditions of the laboratory, much less under field conditions (e.g., outdoor culture ponds) where feedstocks are exposed to highly variable conditions and the crop is vulnerable to invasive species, disease, and grazers. Here, we show that principles from ecology can be used to improve the design of feedstocks and to optimize their potential for “multifunctionality.” We performed a replicated experiment to test these predictions under outdoor conditions. Using 80 ponds of 1,100 L each, we tested the hypotheses that polycultures would outperform monocultures in terms of the following functions: biomass production, yield of biocrude from biomass, temporal stability, resisting population crashes, and resisting invasions by unwanted species. Overall, species richness improved stability, biocrude yield, and resistance to invasion. While this suggests that polycultures could outperform monocultures on average, invasion resistance was the only function where polycultures outperformed the best single species in the experiment. Due to tradeoffs among different functions that we measured, no species or polyculture was able to maximize all functions simultaneously. However, diversity did enhance the potential for multifunctionality—the most diverse polyculture performed more functions at higher levels than could any of the monocultures. These results are a key finding for ecological design of sustainable biofuel systems because they show that while a monoculture may be the optimal choice for maximizing short‐term biomass production, polycultures can offer a more stable crop of the desired species over longer periods of time.  相似文献   
97.
Back calculation, marginal increment analysis and modal progression analysis were used to trace growth processes of the red gurnard, Aspitrigla cuculus L., in the Mediterranean Sea. Three false rings appeared regularly on otoliths and were hypothesized to refer to the ontogeny on the basis of the study of the recruitment and reproduction processes of the species. The first two rings were laid down during the first pelagic period and the transformation to the bottom mode of life, respectively. The third ring corresponded to the first spawning at the end of the second year of life. The marginal increment analysis demonstrated that one opaque and one translucent zone is formed each year, the translucent ring corresponding to the period of slow growth in the winter. Temperature and salinity of Mediterranean waters below the thermocline where red gurnard live do not undergo seasonal variations. Therefore, traditional interpretation of the discontinuity patterns on otoliths related to the decrease of water temperature should be rejected for Mediterranean fish distributed on the deep shelf and slope. Discontinuities in otolith structure may be related to seasonal variation in feeding intensity as a consequence of decreases in the benthic mysids biomass and time available to find food due to reduced daylight. Future research should focus on the trophic ecology of the demersal fishes and the seasonal fluctuations of the prey resources during the year in order to assess the role of the food supply with regard to otolith growth patterns in the Mediterranean Sea.  相似文献   
98.
Anti-Ras intracellular antibodies inhibit cell proliferation in vivo by sequestering the antigen and diverting it from its physiological location [Lener, M., Horn, I. R., Cardinale, A., Messina, S., Nielsen, U.B., Rybak, S.M., Hoogenboom, H.R., Cattaneo, A., Biocca, S. (2000) Eur. J. Biochem.267, 1196-1205]. Here we demonstrate that strongly aggregating single-chain antibody fragments (scFv), binding to Ras, induce apoptosis, and this effect is strictly related to the antibody-mediated aggregation of p21Ras. Proteasomes are quickly recruited to the newly formed aggregates, and their activity is strongly inhibited. This leads to the formation of aggresome-like structures, which become evident in the vast majority of apoptotic cells. A combination of anti-Ras scFv fragments with a nontoxic concentration of the proteasome inhibitor, lactacystin, markedly increases proteasome dysfunction and apoptosis. The dominant-negative H-ras (N17-H-ras), which is mostly soluble and does not induce aggresome formation or inhibit proteasome activity, only affects cell viability slightly. Together, these observations suggest a mechanism linking antibody-mediated Ras aggregation, impairment of the ubiquitin-proteasome system, and cytotoxicity.  相似文献   
99.
The history of chemical investigations into the yellow components of turmeric can be traced from 1815. Although the major yellow component of turmeric, curcumin, often is represented as a 1,3-diketone in the solid state and in nonaqueous solution, it exists in the enol form. The struggle to identify the chemical structure of curcumin continued for nearly a century and was complicated by the difficult purification of curcumin and by the presence of two additional yellow components. Food remains the main use for turmeric (old spice); its use as a dye has diminished since the 19th century, but it may have pharmaceutical uses (new spice).  相似文献   
100.
Using ontologies to describe mouse phenotypes   总被引:1,自引:1,他引:0  
The mouse is an important model of human genetic disease. Describing phenotypes of mutant mice in a standard, structured manner that will facilitate data mining is a major challenge for bioinformatics. Here we describe a novel, compositional approach to this problem which combines core ontologies from a variety of sources. This produces a framework with greater flexibility, power and economy than previous approaches. We discuss some of the issues this approach raises.  相似文献   
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